1. Field of the Invention
The present invention relates to an apparatus for the combustion of carbonaceous material in a vertical reaction chamber having a fluidized bed and at least one cyclone separator for collecting and returning solid matter entrained in the combusiton gases to the bed, and to expell cleaned gas.
2. Description of the Prior Art
It is presupposed that a fluidized bed operating with circulating matter is a known technique. The expression carbonaceous material is intended to cover arbitrary kind of fuel. The bed is also supplied with non-combustible matter, for instance limestone, and inert material so that a desired volume of the bed is maintained.
In known plants the separation of solid matter usually occurs outside the reaciton chamber. The location of cyclone separators within the chamber will provide a more compact design. In order that the separated matter really flows out of the cyclone it is essential to prevent an upward flow of gas through the passage transferring the solid matter.